As chief of staff, Boumédiène entered into conflict with the FLN's government-in-exile, the GPRA, which towards the end of the war attempted to dismiss him. He then supported an alliance of FLN politicians against the GPRA's provisional post-independence government, and marched the ALN towards Algiers to occupy it. Ahmed Ben Bella became president, and Boumédiène minister of defense. In this role Boumédiène continued to exercise a powerful influence over the regime, through the Algerian army. To secure his grip over the army, he began promoting and supporting his old friends and colleagues of the Oujda years. These men and their entourage became known as the Oujda group, forming a powerful pro-Boumédiène faction within the political and military ranks of the one-party state, but in their turn dependent on him for their positions.

After rising tension between the two men and their supporters, Ben Bella in 1965 confronted Boumédiène by attempting to dismiss his close associate, foreign minister Abdelaziz Bouteflika, and by announcing that he soon would be reassigning responsibilities within the army. Boumédiène reacted by staging a military coup d'état, in which Ben Bella was "disappeared" (years later, he was released after having been held isolated in house arrest), and taking personal control over the country by means of a military junta. His associates from Oujda now became the pillar of his regime, but as Boumédiène tightened his grip on power, most of the clan's members were gradually purged.

Still, a more generally defined "old guard", including some of the Oujda men, would continue to exercise influence after Boumédiène's death in 1978, over his successor Chadli Bendjedid. Bendjedid consciously strove to marginalise these men, and to replace them with his own loyalists. This policy became informally known as de-Boumédiènisation. The early 1980s therefore marked the end of whatever remained of the Oujda clan as a (somewhat) cohesive faction within Algerian politics, even if FLN "conservatives" favoring Boumédiène-style policies continued to challenge Chadli from within until they were finally purged following the October Riots in 1988.

In 1999, an old Oujda clan stalwart, the former foreign minister Abdelaziz Bouteflika (who, coincidentally, was born in Oujda), made an unexpected comeback, winning the Algerian presidential elections. He had been convicted for corruption in 1981, soon after Chadli's takeover, in what was viewed as one of the most important steps of de-Boumédiènisation, and in 1983 he had gone into exile. Bouteflika was reelected for a second term in 2004, and then, for a third term, in 2009.